Rotary-engine rotors



Jan 24, 1967 G. DE coYE DE CASTELET 3,299,864A

ROTARY-ENG INE ROTORS Filed Oct. 4, 1965 Mhjr nited States Patent C3,299,864 ROTARY-ENGINE ROTORS Gatan de Coye de Castelet, Billancourt,France, as-

signor to Regie Nationale des Usines Renault, Billancourt, France FiledUct. 4, 1965, Ser. No. 492,621 Claims priority, application France, Nov.13, 1964, 994,904, Patent 1,422,344 1 Claim. (Cl. 12S-S) This inventionrelates to rotary-engine rotors cooled by a cooling liquid flowingthrough a peripheral passage, and more particularly to improvements in`design aimed at ensuring more effective cooling.

It is customary to stiften the wall forming the outer contour of therotor by means of ribs which are parallel to the rotor bisecting planeand therefore ylocated inside the peripheral passage, parallel with thedirection of flow of the cooling liquid.

This flow is consequently of a laminar character and the heat transfercoeicient between the liquid and the hot wall is low.

Now it is Well known that this coefficient is considerably augmentedwhen the ow is made turbulent. Systematic experiments have demonstratedthat:

the heat transfer coefficient is greatly improved when the longitudinalribs are replaced by staggered spikes; and that the best coeicent isobtained when the ribs are arranged transversely in zig-zag fashion onthe two walls of the passage.

These solutions cannot, however, be applied in practice, as the formerfails to impart adequate rigidity to the casting while the latter isvery diicult to carry into practice.

The present invention provides a solution the effectiveness of whichlies intermediate the two solutions referred to and which consists ininterconnecting the two walls of the peripheral passage by means ofstaggered columns.

This invention relates to rotary-engine rotors embodying thisimprovement.

The invention will now be more particularly described with reference tothe accompanying nonlimitative exemplary drawing of a rotary-enginerotor of the four-lobed type, in which:

FIGURE 1 is a cross sectional-view of the rotor;

FIGURE 2 is a half-section taken through the line II- II of FIGURE 1;

FIGURE 3 is a section take through the line III- III of FIGURE l; and

FIGURE 4 is a developed section through the bisecting plane IV-IV of theperipheral passage.

As FIGURE 1 clearly shows, the rotor consists essentially of a rim 1 anda `hub 2.

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Rim 1 has, coextensive therewith either over its entire perimeter orlevel only with the lobes involved in the explosions as shown in thefigure), an inner wall 3 connected to the rim by lateral walls 31 and32, thereby forming a peripheral passage 4 through which the coolingliquid flows.

This liquid is conveyed, for instance, to the apex of the lobe through ahollow arm or spoke 5 and is discharged at the ends of the lobe throughhollow spokes 6 and 7.

The present invention consists in replacing the customary arrangement(in accordance with which the rim 1 is stiened by ribs parallel to thedirection of ow of the liquid, i.e. in this case parallel to thebisecting plane of the rotor) by staggered columns 3.

Thus, as is more particularly shown on FIGURES 2, 3 and 4, provision maybe made, for instance, for five rows of columns. At the places wherethey cannot be provided, for example at the outlets of the hollowspokes, the columns are rep-laced by spikes 9 devoid of contact with thewall 3.

Consequently, all other things being equal, cooling is improved, that isto say that the temperature rise in the rotor is smaller than with thecustomary arrangement in which the rim is stiffened by ribs.

I claim:

A rotary-engine rotor comprising a peripheral passage `which is formedby the rotor rim and an inner Wall connected thereto by lateral wallsand through which ows a cooling fluid, characterized in that the innerrim surface forming the outer wall of said passage is connected to saidinner wall by staggered columns, it being possible for said columns tobe replaced locally by spikes at points where said inner wall is absent.

References Cited by the Examiner UNITED STATES PATENTS 3,102,682 9/ 1963Paschke 23 0-145 3,111,884 11/1963 Peras 123-8 3,112,870 12/1963 Bentele230-210 3,131,679 5/1964 Peras 103-130 3,176,915 4/1965 Bentele et al230210 3,204,614 9/1965 Huber 230-210 3,206,109 9/1965 Paschke 230-145FOREIGN PATENTS 1,359,797 3/1964 France. 1,372,662 8/1964 France.

978,210 12/1964 Great Britain.

992,419 5/ 1965 Great Britain.

DONLEY I. STOCKING, Primary Examiner.

W. I. GOODLIN, Assistant Examiner.

